Is Sitagliptin Effective for Modulating Metabolic Disturbances Associated With Olanzapine in Schizophrenia Patients? A Double-blind Placebo-controlled Clinical Trial

Purpose/Background The mortality rate of patients with schizophrenia due to metabolic disturbances is high. Our aim is to survey the effects of sitagliptin on metabolic disturbances associated with olanzapine in patients with schizophrenia. Methods/Procedures In this 12-week double-blind placebo-controlled clinical trial, 71 patients taking olanzapine (10 to 30 mg) for at least 1 month were randomly allocated to enter 1 of the 2 treatment groups (olanzapine plus placebo or olanzapine plus sitagliptin). Sitagliptin was added to patients 'current medications with the dose of 100 mg/d. Physical examinations and measurement of anthropometric (body mass index and waist circumference) and laboratory parameters (fasting blood sugar, glycated hemoglobin, total cholesterol, low-density lipoprotein, high-density lipoprotein, and triglyceride) were measured at baseline, week 4, and week 12. The patients were assessed for any side effects of the medications in each visit. Findings/Results Sixty-one patients (30 in the sitagliptin and 31 in the placebo group) completed the trial. The anthropometric measurements at the end of the study did not differ between the 2 groups. glycated hemoglobin and total cholesterol were significantly lower in the sitagliptin group after 12 weeks. Other metabolic profile revealed either no change or minimal magnitude changes. No major side effect was reported. Implications/Conclusions Metabolic disturbances associated with olanzapine treatment in patients with schizophrenia can be modulated by sitagliptin.